日期:2014-05-20 浏览次数:20910 次
public class TestDeadLock implements Runnable{
    public int flag = 2;
    static Object o1 = new Object();
    static Object o2 = new Object();
    
    public void run(){
        if(flag == 1){
            synchronized(o1){
                System.out.println("锁住o1");    
                try {
                    Thread.sleep(5000);
                }catch(Exception e){}
            }
            
            synchronized(o2){
                System.out.println("1");
            }
        }
        //疑问:无法死锁
        if(flag == 0){
            synchronized(o2){
                System.out.println("锁住o2");
                try {
                    Thread.sleep(5000);
                }catch(Exception e){}
            }
            
            synchronized(o1){
                System.out.println("2");
            }
        }
    }
    
    public static void main(String[] args){
        TestDeadLock td1 = new TestDeadLock();
        TestDeadLock td2 = new TestDeadLock();
        td1.flag = 1;
        td2.flag = 0;
        Thread t1 = new Thread(td1);
        Thread t2 = new Thread(td2);
        t1.start();
        t2.start();
    }
}
public class TestDeadLock implements Runnable{
    public int flag = 2;
    static Object o1 = new Object();
    static Object o2 = new Object();
    
    public void run(){
        if(flag == 1){
            synchronized(o1){
                System.out.println("锁住o1");    
                try {
                    Thread.sleep(5000);
                }catch(Exception e){}
                
                synchronized(o2){
                    System.out.println("1");
                }
            }
        }
        //疑问:无法死锁
        if(flag == 0){
            synchronized(o2){
                System.out.println("锁住o2");
                try {
                    Thread.sleep(5000);
                }catch(Exception e){}
                
                synchronized(o1){
                    System.out.println("2");
                }
            }
        }
    }
    
    public static void main(String[] args){
        TestDeadLock td1 = new TestDeadLock();
        TestDeadLock td2 = new TestDeadLock();
        td1.flag = 1;
        td2.flag = 0;
        Thread t1 = new Thread(td1);
        Thread t2 = new Thread(td2);
        t1.start();
        t2.start();
    }
}
------解决方案--------------------
顶1 楼的,LZ你的代码,把第二个sychronized 放在外面,这样的话,就不是用sychronized code(同步代码块),用sychronized method(同步函数)来解决,我们平常,写代码,是为了不让其死锁!
------解决方案--------------------